Auntie's Snitch can't block.
Prowl (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Goblin or Rogue.)
Whenever a Goblin or Rogue you control deals combat damage to a player, if Auntie's Snitch is in your graveyard, you may return Auntie's Snitch to your hand.

Trample
When Boldwyr Heavyweights enters the battlefield, each opponent may search his or her library for a creature card and put it onto the battlefield. Then each player who searched his or her library this way shuffles it.

At the beginning of your upkeep, reveal the top card of your library. If it's a land card, put it into your graveyard and repeat this process.
Whenever a land card is put into your graveyard from anywhere, put a +1/+1 counter on Countryside Crusher.